Nanotechnology Can Be a More Efficient Solution for Clean and Safe Water

Image credit: American Chemical Society

The global problem of the scarcity of potable water is something that cannot be ignored. That’s why several continuous research on clean water are being undertaken worldwide. Thankfully, even at this late part of the year, a group of researchers from the California NanoSystems Institute (CNSI) at the University of California – Los Angeles (UCLA) have discovered a method to employ enzymes in the removal of pollutants from water. This method is capable of removing multiple pollutants at once, producing clean water that can be used for irrigation, recreation, and human consumption.

New Approach to Using an Already Existing Method

This method developed by UCLA researchers is not entirely new. There have already been previous methods involving the use of enzymatic activities (through naturally occurring bacteria and fungi). These methods facilitate the breakdown of pollutants into components that can already be considered harmless. However, while these methods are found effective, they come with the risk of contamination. They cannot guarantee that unsafe or even life-threatening organisms are not able to infect the water.

The new method found by UCLA researchers incorporates nanotechnology. The team, composed of UCLA Associate Professor of Civil and Environmental Engineering Shaily Mahendra, Biological Chemistry professor Leonard Rome (also the associate director of CNSI), Danny Abad and Meng Wang of UCLA Department of Civil and Environmental Engineering, experimented with enzymes and nanoscale particles they referred to as “vaults.” The details of this new method are described in an article on the journal ACS Nano.

Nanotechnology for Safe and Clean Water

So how does this nanotechnology-enhanced water treatment work?

In an interview with Phys.org, Mahendra pointed out how natural microbes are responsible for the natural elimination of dinosaur droppings. Mahendra says that they are the reason “why the world isn’t still covered with dinosaur droppings.” These microbes make use of enzymes to disintegrate wastes and pollutants so they don’t end up contaminating bodies of water.

The method, as mentioned earlier, makes use of “vaults” designed to contain the enzymes necessary to degrade the pollutants in water. The “vaults” are extremely tiny particles, only a few nanometers across. They look like beer kegs capable of keeping the enzymes intact and protecting their potency as they are introduced to the contaminated water.

It’s as simple as that. The researchers simply created the “vaults” to be mixed with the microbial enzymes and introduced to the contaminated water. The specific enzyme they used is called manganese peroxidase, a member of the family of oxidoreductases best known for being secreted by the white rot fungi to facilitate lignin degradation.

How Effective Is It?

Based on the tests conducted by the researchers, over a 24-hour duration, the enzymes they mixed with the “vaults” eliminated thrice the amount of phenol from the water as compared to the enzyme used without the “vaults.” The researchers, moreover, observed that the enzymes maintained their stability while they were inside the “vaults,” as these enzymes continued to be capable of removing phenol from water even after 2 days. In contrast, the enzyme used without the vaults became completely inactive after only around 7.5 hours.

What Are the “Vaults” Made of?

The vault nanoparticles are created using proteins. They actually have naturally occurring counterparts found in the cells of almost all living organisms. They were discovered in the 1980s by Leonard Rome (CNSI associate director) and his then postdoctoral student Nancy Kedersha. Decades after the discovery, Rome and his colleagues headed by associate researcher Valerie Kickhoefer have developed a technique for creating empty “vaults” that can become useful in drug delivery, specifically to fight cancer, HIV, and other critical diseases. Now, these empty vaults are not just only useful in drug delivery, they can also used for cleaning contaminated water.

Image credit: Owais Khursheed via Wikimedia Commons

Extent of Application

According to Mahendra, the method they developed can be scaled up for commercial application. It can be a good solution for cleaning up polluted lakes and rivers. Likewise, the vaults can be used together with the membrane filtration units of water treatment facilities. What makes this new method advantageous is that it can be more efficient and cheaper compared to similar earlier approaches in doing water treatment. Also, the “vaults” are unlikely to endanger humans and the environment.

This is not the first time that nanotechnology is being used in water treatment. Around two years ago, a nanotech water filter was already created. The difference this time, though, is that there is a biological aspect involved. This new technique is something that is bound to become highly useful so hopefully it can be commercialized soon.